Many articles exist that maintain a generally airtight or hermetic seal, or at least remain in an enclosure, in order to function properly. It may be desirable to test the internal characteristics of such an article, such as material consistency, fluid levels, and the like, to determine whether the article is to be replaced and/or repaired. According to conventional methods, the article may be subjected to more invasive tests.
Such methods may run the risk of rendering the article unfit for its intended purpose. Further, such methods may be expensive and/or difficult to carry out. It may be desirable to engage in periodic examination of the internal characteristics of the article, but repeated performance of such testing may multiply the expense and/or inconvenience.
One type of article for which examination of internal characteristics may be desired is a battery, or more specifically, a lithium-ion battery. Lithium-ion batteries may generally maintain a hermetic seal in order to operate properly. Additionally, the batteries may contain electrolytes and other materials that can degrade under the stresses of operation, particularly in the context of aviation. Such stresses may include ambient pressure cycles if the batteries are positioned in an unpressurized part of the aircraft. Additionally, such stresses may include dramatic temperature cycles and/or duty cycles as the aircraft's electrical components are activated and deactivated. Such batteries may be important for the operation of the aircraft's electrical systems.
Accordingly, it is desirable to regularly check the internal characteristics of such batteries. It is further desirable for the testing method used to be non-destructive so that batteries that have passed the test may be readily re-used. Further, it is desirable for the testing method to be rapidly and inexpensively carried out. Yet further, it is desirable for the testing method to be reliable and accurate so that faulty batteries can be easily detected and repaired and/or replaced